The invention relates generally to circular saws and more particularly it relates to a method of and a device for correcting play in mechanical feeding means for a cold action circular saw, particularly of the type having a swingable saw arm hinged to a saw table and a power transmitting mechanism constituted of two parts movable one against the other on a rectilinear path, such as for example a rack and pinion mechanism or a screw spindle mechanism with a nut or the like, is hinged between the free end of the saw arm and the socket of the machine base.
The rigidity of the feed or advance of the saw blade is especially in the case of cold action circular saws of greater importance for achieving both a high cutting efficiency and a long edge life of the saw blade. It is known to use hydraulic cylinder-and-piston units as feeding means, nonetheless in these hydraulic units vibrations can take place due to the elasticity of the pressure medium in the working cylinder and in the hoses. For this reason it is also known to use mechanical feeding means for feeding the saw blade, such as for example a screw spindle engaging nut, which similarly as the aforementioned hydraulic cylinder can be arranged between the socket of the machine base and the saw arm of the cold action circular sawing machine. These mechanical feeding means considerably improve the rigidity of the feeding drive.
In the feeding device for the saw blade of a cold action circular saw, the movable connecting piece between the socket and the saw arm is intermittently subject to a pressure load and also to a tension load. The pressure load results due to the weight of the saw arm. Moreover, due to the cutting forces taking place on the saw teeth and due to their components formed by the inclination of the teeth, there temporarily result further pressure forces, and also temporary additional tension forces. If the movable connecting members of the feeding means are not completely rigid, these forces may cause vibrations and chatter in the saw blade resulting in an excessive wear of the latter.
Even when using as a feeding means a spindle in engagement with a rolling ball nut, the aforementioned danger is not always excluded, since the hinges and also the ball nut are not without play. The backlash free adjustment of these different parts of the mechanical feeding device requires, however, additional expenditures and from time to time also necessitates a corresponding after adjustment.